In the present work, the diffusion of gallium in germanium substrates at low (5x10(13) cm(-2)) and high (1x10(15) cm(-2)) implantation doses is investigated for temperatures ranging between 550 and 650 degrees C and times of up to 240 min. At a low dose, negligible diffusion is observed for annealing temperatures of up to 600 degrees C for 3 h. For higher temperatures, diffusion toward the surface was observed. For the high dose case, two regions can be identified: an immobile part near the peak and a diffusing part at the tail of the Ga profiles. Such behavior could be indicative of a Ga clustering mechanism.